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Abstract: A novel tertiary amine squaramide has been successfully developed and applied to catalyze the asymmetric Michael addition between cyclic diketones and β,γ-unsaturated α-ketoesters. The catalyst system performed well with a low catalyst loading of 1 mol% under mild reaction conditions. A series of synthetically and pharmaceutically useful chiral bicyclic compounds were obtained with both high yields (up to 97%) and excellent enantioselectivities (up to 97% ee).

Abstract: A new tertiary amine-thiourea organocatalyst has successfully been developed and applied into the asymmetric Michael addition of pyrazolin-5-one to nitroalkenes. The catalyst system performed well with a low catalyst loading of 5 mol% under mild reaction conditions. A series of synthetically and pharmaceutically useful chiral pyrazolone derivatives was obtained in high yields (up to 95%) with good enantioselectivities (up to 88 % ee).

Abstract: A highly stereoselective methodology was developed to construct dihydrofurans. In the presence of a bifunctional squaramide catalyst, the Michael addition/cyclization between cyclohexane- 1,3-dione and α-bromonitroalkenes occurred smoothly to provide the desired dihydrofurans with high to excellent yields (90-94%) and good to high enantioselectivities (80-94% ee). This catalytic protocol was compatible with a range of structurally distinct α-bromonitroalkenes.

Abstract: The isosteviol derived bifunctional primary amine-squaramide organocatalysts were applied in the Michael addition between nitroalkenes and acetophenone. The conjugate addition isomers of two configurations were observed with high yields (up to 93% yield) and good enantioselectivity (up to 91% ee) at room temperature.

Based on the first-principles method of density Functional Theory (DFT), a scandium atom doped twodimensional MoS2 model was constructed in this paper. The adsorption behavior of CO2 and SO3 on the surface of intrinsic MoS2 and Sc–MoS2 were studied, and the adsorption structure and electronic properties of the adsorption system were calculated. The results show that the geometric structure of the adsorption of CO2 and SO3 by intrinsic MoS2 changed a little, the adsorption energy is −0.756 eV and −0.910 eV, respectively. The band gap width does not change significantly. After Sc doped in MoS2, the binding energy of Sc–MoS2 is −1.115 eV, the band gap width changes from 1.720 eV to 0.323 eV, which reduced significantly. At the same time, combined with the electron fractal wave state density diagram, it is found that the electrons at Fermi level are mainly provided by Sc, which indicated that doping contributes to improve the system conductivity. After the adsorption of CO2 and SO3 by Sc–MoS2, the geometric structure of the former changed a little, the adsorption energy is −0.383 eV, and the forbidden band width changes little. The geometric structure of the latter changes significantly, the Sc–S bond length is elongated, SO3 changes from a plane equilateral triangle to a pyramid shape, the adsorption energy is −4.823 eV, the forbidden band width becomes negative, the conductivity of the system is significantly improved, but it is difficult to decompose.

Carbon neutrality is one of ultimate goals of global population. The detection of CO2, now, is a research hotspot, and two-dimensional materials are undoubtedly play an important role. In this paper, the first-principles approach based on density functional theory was used to study the adsorption behavior of CO2 on intrinsic and defective g-GaN. The results are as follows. The adsorption energy is relatively bigger, the band gap and the structures of g-GaN and CO2 have no obvious changes when CO2 is adsorbed on the intrinsic g-GaN. It indicates that intrinsic g-GaN is inert to CO2. Defective g-GaN still maintains a planar structure, but g-GaN are transformed from semiconductors to half-metal and metals after the introduction of Ga and N single vacancies, respectively. The CO2 adsorption energy and adsorption distance are reduced, the structure of defective g-GaN is obviously deformed when CO2 is adsorbed on defective g-GaN. It indicates that the adsorption between g-GaN and CO2 is stronger. CO2 is physically adsorbed on these three structures from the perspective of charge exchange which is good for desorption. Defective g-GaN still remain half-metallic and metallic properties after CO2 is adsorbed on it. From the adsorption energy, the introduction of Ga vacancy enhances the detection ability of g-GaN for CO2, and it is better than N vacancy. This provides theoretical support for g-GaN materials as a nanoscale gas sensor materials.

A new tertiary amine-squaramide organocatalyst has been developed and applied to the asymmetric Michael addition of cyclic diketones to β,γ-unsaturated α-keto esters. The catalyst system performed well with a low catalyst loading of 1 mol% under mild reaction conditions. A series of synthetically and pharmaceutically useful chiral bicyclic compounds were obtained in high yields (up to 97%) with excellent enantioselectivities (up to 99 % ee). Furthermore, this catalytic system can be used efficiently in large-scale reactions with the yields and enantioselectivities being maintained.

Chiral amine-squaramide is a kind of effective hydrogen bond donor bifunctional catalyst to promote many asymmetric transformations. In this paper, novel chiral tertiary amine-squaramide derived from the natural product of the stevioside was developed and applied into the asymmetric Michael addition of acetylacetone to nitroolefins. This asymmetric reaction performed well, and a series of enantiomerically enriched compounds were obtained in high yields (up to 96%) with excellent enantioselectivities (up to 99% ee).

The convenient preparation of N2-unprotected five-membered cyclic guanidines was achieved through a cascade [3 + 2] cycloaddition between organo-cyanamides and α-haloamides under mild conditions in good to excellent yields (up to 99%). The corresponding cyclic guanidines could be easily transformed into hydantoins via hydrolysis.

The management of biopsy proven atypical lobular hyperplasia (ALH) is controversial. Although upgrade rates are low, excisional biopsy is often performed to rule out occult breast cancer. In this study, we analyzed our experience with excisional biopsy for ALH diagnosed in the digital tomosynthesis era with radiographic concordance in the community hospital setting. This study included 93 consecutive patients diagnosed with pure ALH on core biopsy from January 2013–December 2017 who underwent subsequent excisional biopsy. Potential clinical, radiographic and pathologic predictors of upgrading were analyzed. At the time of excisional biopsy, five patients (5.4%) were upgraded to DCIS or invasive breast cancer. There was also a trend towards higher upgrade rates in patients with contralateral breast cancer (p = 0.06), biopsy performed by ultrasound or MRI (p = 0.07) and extensive ALH (p = 0.10). Other clinical, radiographic and pathologic variables were not predictive of upgrade rate (p > 0.1 for all). Patients with pure ALH with radiographic concordance have a low risk of pathologic upgrading on excisional biopsy. Potential predictors of upgrade rate warrant further analysis in a larger dataset.

Aspidopterys obcordata vine is a Chinese Dai ethnic herb used to treat urolithiasis. However, the material basis and underlying mechanisms remain undefined. In this study, a 2.3 kD inulin-like A. obcordata fructan (AOFOS) was isolated by size exclusion column chromatography and characterized by ultrahigh-performance liquid chromatography-ion trap-time of flight mass spectrometry (UPLC-IT-TOF-MS), nuclear magnetic resonance (NMR) spectroscopy, gas chromatography mass spectrometry (GC-MS) and high-performance gel permeation chromatography (HGPC). In addition, AOFOS showed unique anti-urolithiasis activity in Drosophila kidney stone models. Mechanism study indicated that AOFOS reduced the size of calcium oxalate crystals by inhibiting the formation of large size crystals and the generation rate of calcium oxalate crystals as well as the crystal form conversion from calcium oxalate monohydrate (COM) to calcium oxalate dihydrate (COD).

Atypical ductal hyperplasia (ADH) is an indication for excisional biopsy to rule out occult breast cancer. We analyzed pathological findings on excisional biopsy for ADH diagnosed in a high volume breast center equipped with digital tomosynthesis. Two hundred consecutive patients were diagnosed with ADH on core biopsy with radiographic concordance followed by excisional biopsy. On excisional biopsy, 33 patients (16.5%) were diagnosed with DCIS or invasive breast cancer. Patients with a concurrent diagnosis of papilloma had a higher risk of upstaging on both univariate and multivariate analysis (41.7% vs. 14.9%, p=0.015). No other statistically significant predictors of upgrading were identified (p>0.05).

Background The indication of retroperitoneal laparoscopic adrenalectomy (RLA) was extended with the retroperitoneal approach and has been wildly accepted and technologically matured. However, the management of large adrenal tumors via this approach still remains controversial. The aim of this study was to perform a comprehensive analysis on the minimally invasive surgical management of larger adrenal tumors. Methods A total of 78 patients with large adrenal tumors (> 5 cm) and 97 patients with smaller adrenal tumors ( 5 cm) group showed superior results for the intraoperative indicators than the smaller tumor ( 0.05). Data confirmed that the partial resection method was superior to the total resection method from the perspective of the hormone supplement (0% vs. 48.15%, P = 0.002). The 2-year recurrence-free rates were 92.60 and 92.86% for the total and partial RLA resection methods, respectively (P = 0.97). The partial RLA resection method had a similar complete remission rate as the total RLA resection method (96.30% vs. 100%, respectively, P = 0.47). Conclusion Both RLA and TLA seem to provide similar effects for the surgical management of large adrenal tumors. However, partial RLA resection should be considered for the management of benign tumors to reduce the hormone supplement. Electronic supplementary material The online version of this article (10.1186/s12894-018-0349-0) contains supplementary material, which is available to authorized users.

The radiation-driven tearing mode (RTM) in tokamaks was numerically studied in our previous investigation (Xu et al 2020 Plasma Phys. Control. Fusion 62 105009), and it was noticed that radiation cooling could drive magnetic island growth and could even cause disruption due to the nonlinear mode coupling. In this work, the suppression of the radiation-driven m / n = 2 / 1 tearing mode by an externally driven current is investigated numerically by using a three-dimensional toroidal code CLT (Ci-Liu-Ti means magnetohydrodynamics in Chinese) based on a full set of resistive magnetohydrodynamic equations. It is found that an externally driven current with appropriate turn-on time and strength can effectively stabilize the RTM. The effects of the asymmetry current and multi-mode coupling can be stabilized effectively by the externally driven current. In the nonlinear stage, under the influence of the radiation, a strong m / n = 1 / 0 mode is generated due to the hot-core shift caused by the decrease of the core thermal pressure, which is irreversible even if the m / n = 2 / 1 magnetic island could be effectively controlled by the externally driven current. When the externally driven current is turned on in the linear stage, it very efficiently and quickly suppresses the dominant modes, and the hot-core shift effect also becomes weaker because of the smaller m / n = 1 / 0 mode. Moreover, it is found that external auxiliary heating with appropriate intensity in the core region can effectively balance the reduced pressure and can further control the hot-core shift caused by radiative cooling.

New bifunctional primary amine-squaramides catalyzed asymmetric Michael addition reaction of α,α-disubstituted aldehydes to maleimides has been developed. This organocatalytic asymmetric reaction provides easy access to functionalized succinimides with a broad substrate scope. Both enantiomers of desired succinimide derivatives were obtained in good to excellent yields (up to 98%) with excellent enantioselectivities (up to >99% ee).

The models and influencing factors of steel ladles exchange during the steelmaking and continuous casting process of H steel plant were investigated. Based on analysis of the operation process and turnover time of steel ladles, relationship models for the turnover number, turnover rate, continuous casting number, number of ladles with additional turnover, and number of ladles without additional turnover were built. The turnover rules of steel ladles for one basic oxygen furnace (BOF) matching one continuous caster (CC) and two BOFs matching two CCs modes were simulated by using a Gantt chart. The models of steel ladle exchange were proposed for casting of a single CC and overlapping casting of two CCs. By analyzing the influencing factors, the following conclusions were drawn. The exchange ladle should not have the task of transporting liquid steel in the CC that stops casting earlier. The end time of the empty ladle in the CC that stops casting earlier should be earlier than the start time of the full ladle in the CC that stops casting later. After evaluating the factors influencing the start casting time, turnover cycle, casting time, continuous casting number, and overlapping time, a prioritization scheme of steel ladle exchange was proposed based on the steel grade. First, the turnover cycle and single heat casting time were determined; based on these, a reasonable ladle turnover number was calculated. Second, the turnover number and continuous casting number were optimized for maximizing the number of ladles without additional turnover. Lastly, to reduce the casting number during the overlapping time to be lower than the turnover number, the overlapping time was shortened.

The covalently cross-linked chitosan-poly(ethylene glycol)1540 derivatives have been developed as a controlled release system with potential for the delivery of protein drug. The swelling characteristics of the hydrogels based on these derivatives as the function of different PEG content and the release profiles of a model protein (bovine serum albumin, BSA) from the hydrogels were evaluated in simulated gastric fluid with or without enzyme in order to simulate the gastrointestinal tract conditions. The derivatives cross-linked with difunctional PEG1540-dialdehyde via reductive amination can swell in alkaline pH and remain insoluble in acidic medium. The cumulative release amount of BSA was relatively low in the initial 2h and increased significantly at pH 7.4 with intestinal lysozyme for additional 12h. The results proved that the release-and-hold behavior of the cross-linked CS-PEG1540H-CS hydrogel provided a swell and intestinal enzyme controlled release carrier system, which is suitable for oral protein drug delivery.

Objective. The objective of this study was to investigate the expression of telomere repeat binding factor 1 (TRF1) and TRF2 in prostate cancer and their relationships with clinicopathological features. Methods. In total 50 prostate cancer tissues and paired benign prostate hyperplasia tissues were analyzed. The telomere-binding proteins TRF1 and TRF2 were measured using immunohistochemical method. Correlation analyses were used to evaluate the association between immunohistochemical score and clinical parameters. Results. The expression of TRF1 was significantly higher in prostate cancer tissue than in benign prostate hyperplasia tissue (χ2 = 62.69, P<0.01). Elevated levels of TRF2 were observed in both prostate cancer and benign prostate hyperplasia tissue (χ2 = 1.13, P=0.76). TRF1 expression was significantly positively correlated with surgical capsular invasion (Spearman’s r=0.43, P=0.002), seminal vesicle invasion (Spearman’s r=0.35, P=0.01), lymph nodes metastases (Spearman’s r=0.41, P=0.003), total prostate specific antigen (r=0.61, P<0.05), and Gleason score (r=0.47, P=0.01). However, there were no significant statistical differences between prostate volume (r=0.06, P=0.75) and age (r=0.14, P=0.09). Conclusion. Both TRF1 and TRF2 were overexpressed in prostate cancer. There was no specificity of TRF2 in prostate cancer, while TRF1 may be associated with prostate cancer progression.

A highly efficient domino aza-MIRC (Michael Induced Ring Closure) reaction between barbiturate-derived alkenes and N-alkoxy α-haloamides has been achieved in moderate to excellent yields. This reaction proceeds smoothly under mild conditions via a domino aza-Michael addition/intramolecular SN2 sequence, providing a practical tool in the synthesis of bioactive molecules spirobarbiturate-3-pyrrolidinones.

For further research on the control model of multifunctional hot metal ladles between the ironmaking and steelmaking interface, the hot metal ladles of K steel plant were taken as the object to analyze the operation process. The factors of blast furnace supply and basic oxygen furnace demand were proposed. According to the principle of supply and demand balance, the control model of hot metal was researched under the following factor conditions: equal to, greater than, and less than 1, respectively. The distribution model of the blast furnace, steelmaking works, and online buffering was proposed. When the supply and demand factor is equal to 1, the turnover number of hot metal ladles equals 16 and the turnover cycle of hot metal ladles equals 512 min. When the factor is greater than 1, the total number of hot metal ladles is equal to the normal turnover number plus the turnover number of the cast iron machine. When the factor is less than 1, the total number of hot metal ladles is equal to the normal turnover number plus the accumulating number. Satisfactory effects were obtained by applying the control model in production. The numbers of turnover ladles and accumulating ladles were reduced.

Chiral primary amine–squaramides have not been extensively studied to date in the field of organocatalysis. In this paper, novel chiral squaramides derived from natural product stevioside were developed. Both enantiomers of a series of γ-nitroaldehydes were generated by using these squaramide catalysts for the Michael addition reaction of isobutyraldehyde to nitroolefins. This asymmetric reaction proceeded well to afford the desired products in high yields (up to 98%) with high to excellent enantioselectivities (up to 99% ee).

Objective To observe the effect of combining Chinese medicine and tuina along the meridians on motor function and activities of daily living (ADL) in patient with post-stroke upper limb spasticity

BACKGROUND The purpose of this study was to investigate the value of mean platelet volume (MPV) for prognosis of patients with acute cerebral infarction (ACI). METHODS One hundred ACI patients and 80 healthy volunteers acting as healthy controls (HCs) were consecutively included in this study. Their baseline clinical and laboratory characteristics were extracted from an electroniccase system. ACI patients were followed for 90 days to collect the main study endpoints including poor prognosis, death due to cardiovascular causes, and the recurrence of stroke. ACI patients were evaluated after 7 days in the hospital using the National Institute of Health Stroke Scale (NIHSS) score to evaluate stroke severity on admission and using the modified Rankin Scale (mRS) to evaluate functional disorders. Receiver operating characteristic (ROC) curve analysis was used to estimate the predictive value of MPV on ACI. Kaplan-Meier survival analysis and Cox regression models were used to analyse the value of MPV as a predictor of ACI. RESULTS This study suggested that MPV and rate of hypertension were higher in ACI patients than in the HC group. In the follow-up period, 32 ACI patients suffered study endpoints; they had higher average MPV, NIHSS scores, longer ACI onset times, and shorter event-free survival time compared to control patients. ROC curves showed that MPV was an index for prognosis of ACI patients with an AUC of MPV of 0.82 (95% confidence interval (CI): 0.74 - 0.90), and the best cutoff was 10.05 fL. MPV, NHISS scores, age, and TG were independent risk factors for endpoints of ACI patients. MPV with hazard ratio (HR) was 1.94 (95% CI, 1.37 - 2.72, p = 0.000), NIHSS score with HR was 1.22 (95% CI, 1.03 - 1.44, p = 0.021), age with HR was 1.06 (95% CI, 1.00 - 1.11, p = 0.038), and TG HR was 0.60 (95% CI, 0.36 - 1.00, p = 0.048) using Cox regression models. P  0.05 for all groups was considered statistically significant. CONCLUSIONS Mean platelet volume was an independent risk factor and serves as a sensitive index for the prognosis of ACI patients.

Amyloid β-peptide (Aβ) has been implicated as a key molecule in the neurodegenerative cascades of Alzheimer's disease (AD). Humanin (HN) is a secretory peptide that inhibits the neurotoxicity of Aβ. However, the mechanism(s) by which HN exerts its neuroprotection against Aβ-induced AD-like pathological changes and memory deficits are yet to be completely defined. In the present study, we provided evidence that treatment of rats with HN increases the number of dendritic branches and the density of dendritic spines, and upregulates pre- and post-synaptic protein levels; these effects lead to enhanced long-term potentiation and amelioration of the memory deficits induced by Aβ(1-42). HN also attenuated Aβ(1-42)-induced tau hyperphosphorylation, apparently by inhibiting the phosphorylation of Tyr307 on the inhibitory protein phosphatase-2A (PP2A) catalytic subunit and thereby activating PP2A. HN also inhibited apoptosis and reduced the oxidative stress induced by Aβ(1-42). These findings provide novel mechanisms of action for the ability of HN to protect against Aβ(1-42)-induced AD-like pathological changes and memory deficits.

Chitosan has previously been exploited as a scaffold in tissue engineering processes. To avoid infection, chitosan must be sterilized prior to contact with bodily fluids or blood. Previous research has shown that autoclaved chitosan solution lead to decreased molecular weight, dynamic viscosity, and rate of gelling. We prepared a thermosensitive chitosan hydrogel using autoclaved chitosan powder (121 °C, 10 min) and β-glycerophosphate (chitosan-PA/GP) and compared the physicochemical properties and biocompatibility in vitro with autoclaved chitosan solution/GP hydrogel. The chitosan-PA/GP hydrogel had a shortened gelation time, higher viscosity, increased water absorption, appropriate degradation time, porous structure, and no obvious cytotoxicity on human periodontal ligament cells. Scanning electron microscopy demonstrated that the cells exhibited a normal morphology. The chitosan-PA/GP hydrogel promoted periodontal tissue regeneration in dog class III furcation defects. The chitosan-PA/GP thermosensitive hydrogel displayed suitable physicochemical properties and biocompatibilities and represents a promising candidate as an injectable tissue engineering scaffold.

Vitamin D has important biological functions including modulation of the immune system and anti-cancer effects. There was no conclusive finding of the impact of serum vitamin D level on bladder cancer risk. A systemic review and meta-analysis was performed to assess the impact of serum 25-hydroxyvitamin D level on bladder cancer risk. The pooled relative risk (RR) with 95 % confidence interval (95%CI) was used to assess the impact of serum 25-hydroxyvitamin D level on bladder cancer risk. A total of 89,610 participants and 2238 bladder cancer cases were finally included into the meta-analysis. There was no obvious heterogeneity among those included studies (I 2 = 0 %). Meta-analysis total included studies which showed that a high serum 25-hydroxyvitamin D level could obviously decrease risk of bladder cancer (RR = 0.75, 95%CI 0.65–0.87, P

A doubly stereocontrolled organocatalytic asymmetric Michael addition to the synthesis of substituted succinimides is described. Starting from aldehydes and maleimides, both enantiomers of the succinimides could be obtained in high to excellent yields (up to 98%) and enantioselectivities (up to 99%) when one of the two special chiral diterpene-derived bifunctional thioureas was individually used as a catalyst. Moreover, these catalysts can be efficiently used in large-scale catalytic synthesis with the same level of yield and enantioselectivity. Chirality 00:000–000, 2014. © 2014 Wiley Periodicals, Inc.

Patients with diabetes in the aging population are at high risk of Alzheimer's disease (AD), and reduction of sirtuin 1 (SIRT1) activity occurs simultaneously with the accumulation of hyperphosphorylated tau in the AD-affected brain. It is not clear, however, whether SIRT1 is a suitable molecular target for the treatment of AD. Here, we employed a rat model of brain insulin resistance with intracerebroventricular injection of streptozotocin (ICV-STZ; 3 mg/kg, twice with an interval of 48 h). The ICV-STZ-treated rats were administrated with resveratrol (RSV; SIRT1-specific activator) or a vehicle via intraperitoneal injection for 8 weeks (30 mg/kg, once per day). In ICV-STZ-treated rats, the levels of phosphorylated tau and phosphorylated extracellular signal-regulated kinases 1 and 2 (ERK1/2) at the hippocampi were increased significantly, whereas SIRT1 activity was decreased without change of its expression level. The capacity of spatial memory was also significantly lower in ICV-STZ-treated rats compared with age-matched control. RSV, a specific activator of SIRT1, which reversed the ICV-STZ-induced decrease in SIRT1 activity, increases in ERK1/2 phosphorylation, tau phosphorylation, and impairment of cognitive capability in rats. In conclusion, SIRT1 protects hippocampus neurons from tau hyperphosphorylation and prevents cognitive impairment induced by ICV-STZ brain insulin resistance with decreased hippocampus ERK1/2 activity.

Hyperphosphorylated tau aggregated into neurofibrillary tangles is a hallmark lesion of Alzheimer's disease (AD) and is linked to synaptic and cognitive impairments. In animal models, cold water stress (CWS) can cause cognitive disorder and tau hyperphosphorylation. Capsaicin (CAP), a specific TRPV1 agonist, is neuroprotective against stress-induced impairment, but the detailed mechanisms are still elusive. Here, we investigated whether CAP mitigates CWS-induced cognitive and AD-like pathological alterations in rats. The animals were administered CAP (10 mg/kg in 0.2 ml, 0.1% ethanol) or a control (0.2 ml normal saline, 0.1% ethanol) by intragastric infusion 1 h before CWS treatment. Our results showed that CAP significantly attenuated CWS-induced spatial memory impairment and suppression of PP-DG long-term potentiation; CAP abolished CWS-induced dendritic regression and enhanced several memory-associated proteins decreased by CWS, such as synapsin I and PSD93; CAP also prevented CWS-induced tau hyperphosphorylation by abolishing inhibition of protein phosphatase 2A. Taken together, this study demonstrated that activation of TRPV1 can mitigate CWS-induced AD-like neuropathological alterations and cognitive impairment and may be a promising target for therapeutic intervention in AD.

The investigation on the structures, stabilities, and magnetism ofNimAln(m=1–3,n=1–9) clusters has been made by using first principles. We found some new ground-state structures which had not been found before. These mixed species prefer to adopt three-dimensional (3D) structures starting from four atoms. All the ground-state structures for the Ni-Al clusters are different from those of the corresponding pure Al clusters with the same number of atoms except for three atoms. The Mulliken population analysis shows that some charges transfer from the Al atoms to the Ni atoms.NiAln(n = odd number) cations, Ni2Al6neutral, Ni2Al1and Ni3Al cations and anions, and Ni3Al5anion have the magnetic moments of 2 μB. The magnetic moments of NiAl4and NiAl6cluster neutrals and cations are 2 μBand 3 μB, respectively. All the other cluster neutrals and ions do not have any nontrivial magnetic moments. The 3d electrons in Ni atoms are mainly responsible for the magnetism of the mixed Ni-Al clusters.

Chiral isosteviol-derived tertiary amine-thiourea was proven to be effective in catalyzing the asymmetric conjugate addition between α-substituted cyanoacetate and maleimides. Diverse succinimides bearing vicinal quaternary-tertiary stereocenters were obtained in excellent yields, excellent diastereoselectivities, and with good to high enantioselectivities. This catalytic system can be used efficiently in large-scale reactions with the yields and stereoselectivities being maintained at the same level.

For further research on the precondition and interoperability model of interaction ladles among continuous caster, this article takes steel ladle of Y steel works as the object of research. On the basis of turnover number calculation model of single cast steel ladle, the relationship between cast number and the turnover number and turnover times and last turnover number are further analyzed. The simulation of steel ladle turnover rules was taken on the 2 continuous casters with Gantt chart. After that, the relationships between turnover number and last turnover number and non-turnover number are researched deeply. Combining with the Gantt chart, the expressions of start casting time and empty ladle ending time and heavy ladle starting time were put forward. The precondition of steel ladle interaction is obtained, which means the exchange ladle should not undertaking transport task in first stop continuous caster, and the empty ladle end time of exchange ladle of first stop continuous caster should early than the heavy ladle start time of last stop continuous caster. After applying the model to practice, 3 steel ladles of No.2 continuous caster can be reduced. This research results is supplying theoretical basis for steel ladle controlling and production organization optimization, and enriches the theory and method of metallurgical process integration.

By doing modal analysis of the whole wind turbine system, we can get the first twenty orders natural frequencies and corresponding mode shapes, By analyzing the dynamic characteristics of the blade, the weakness points of blade were fund. Under rotor rotating excitation in the normal state, mass eccentricity states and stiffness damage states of blade, the strain energy change rates (SECR) of nacelle are obtained. While based on the SECR of nacelle, the methods of strain energy change rate and support vector machine are introduced to indentify locate the mass eccentricity and stiffness damages of blade. The research show that mass eccentricity and stiffness damages at different location and in different degree can be efficiency identified and forecasted by means of support vector machine classification method.

A novel class of chiral bifunctional thioureas bearing a chiral lipophilic beyerane scaffold and a tertiary amino group was designed and prepared. The thioureas were proven to be effective for catalyzing the doubly stereocontrolled asymmetric Michael addition between acetylacetone and nitroolefins. The corresponding adducts were obtained in high yields (up to 95%) and with good to excellent enantioselectivities (up to 97%). In addition, the reaction of tert -butyl acetoacetate and trans -β-nitrostyrene also proceeded smoothly with good enantioselectivity.

A novel class of chiral multifunctional thioureas bearing a chiral lipophilic beyerane scaffold and a primary amino group were designed and prepared. The thioureas were proven to be effective for catalyzing the asymmetric Michael addition between isobutyraldehyde and maleimides with only 0.5 mol % catalyst loading, and exhibited double asymmetric induction. Both of the catalysts afforded the corresponding adduct with high to excellent yields (up to 98%) and excellent enantioselectivities (up to 99%). Furthermore, this catalytic system can be used efficiently in large-scale reactions with the yields and enantioselectivities being maintained at the same level.

A novel class of chiral amphiphilic bifunctional thioureas based on a beyerane scaffold and each containing a primary amino group were designed and synthesized from the readily available natural product isosteviol. The thioureas were shown to be effective for catalyzing asymmetric Michael additions between isobutyraldehyde and nitroalkenes. The chiral thiourea 1a furnished S enantiomers, whereas 1b afforded R enantiomers, both with high yields (up to 92 %) and high to excellent enantioselectivities (up to 98 %). Furthermore, the reactions proceeded smoothly both in organic solvents and in water under mild conditions.

A series of new polymer-supported palladium complexes with C,N-ligands (1a–e and 2a–c) were easily synthesized. The synthesized catalysts could be applied as efficient heterogeneous catalysts for the Heck coupling reaction (turnover frequency up to 12 600 h−1). Additionally, the catalysts could be recovered by a simple filtration progress and could be reused for at least five times with a slow progressive decrease in activity. Copyright © 2010 John Wiley & Sons, Ltd.

The cellular and molecular events of periodontal healing are coordinated and regulated by an elaborate system of signaling molecules, pointing to a primary strategy for functional periodontal compartment regeneration to replicate components of the natural cellular microenvironment by providing an artificial extracellular matrix (ECM) and by delivering growth factors. However, even with optimal carriers, the localized delivery of growth factors often requires a large amount of protein to stimulate significant effects in vivo, which increases the risk and unwanted side effects. A simple and relatively new approach to bypassing this dilemma involves converting cells into protein producing factories. This is done by a so-called gene delivery method, where therapeutic agents to be delivered are DNA plasmids that include the gene encoding desired growth factors instead of recombinant proteins. As localized depots of genes, novel gene delivery systems have the potential to release their cargo in a sustained and controlled manner and finally provide time- and space- dependent levels of encoded proteins during all stages of tissue regrowth, offering great versatility in their application and prompting new tissue engineering strategy in periodontal regenerative medicine. However, gene therapy in Periodontology is clearly in its infancy. Significant efforts still need to be made in developing safe and effective delivery platforms and clarifying how gene delivery, in combination with tissue engineering, may mimic the critical aspects of natural biological processes occurring in periodontal development and repair. The aim of this review is to trace an outline of the state-of-the-art in the application of gene delivery and tissue engineering strategies for periodontal healing and regeneration.

We study the substorm dipolarization occurring from 1730 to 1930 UT on Sep 14, 2004 based on DSP/TC1, Cluster and Polar data, combined with the aurora and geosynchronous energetic particle measurements and ground-based magnetic field observations. During this time period the IMF was continuously southward. Substorm onset started at about 1822 UT. Three minute later at 1825 UT TC1, which was located at (–10, –2, 0) RE (GSE) in the near-Earth tail, saw a sharp decrease of magnetic BX component, accompanied by sudden increases in both the ion temperature and thermal pressure. Two minutes further later, energetic electron injection was observed by LANL-02A in the pre-midnight sector at geostationary orbit. About 23 minutes later at 1850 UT, the same signatures as observed by TC1 were observed by Cluster at (–16, 1, 3) RE (GSE) in the mid-tail. Meanwhile, POLAR, which was located much higher and more close to the Earth at (–7.5, 3.5, –4.0) RE (GSE), saw a sudden change in the elevation of the magnetic field at about 1855UT. Aforementioned time sequence of substorm activities indicates that the expansion onset took place at about 1822UT and TC1 and Cluster observed dipolarization (tail expansion) 3 and 28 minutes later, respectively. This means that tail expansion was propagated from source region in the near-Earth tail to the mid-tail. Detailed calculations imply that the source of the dipolarization was situated at about X = −(8.5 − 8.7) RE and the tailward progression speed was about (70~82) km·s-1. A substorm paradigm is proposed to explain the observations in this substorm event: Earthward flow produced by magnetic reconnection in the mid-tail creates favorable conditions for substorm initiation in the near-Earth; after the expansion onset the dipolarization front propagates down to the tail.

Background: Aggressive periodontitis (AgP) has a genetic basis. It has been reported that the functional gene polymorphisms of matrix metalloproteinase (MMP)-2, MMP-9 and tissue inhibitor of metalloproteinase-2 (TIMP-2) alter their expressions in transcriptional level and they are involved in the tissue destruction of periodontitis. The study was carried out to analyse the association of functional polymorphisms in MMP-2, MMP-9 and TIMP-2 with generalized AgP (G-AgP) in a Chinese population. Material and Methods: The study population consisted of 79 Chinese patients with G-AgP and 128 healthy controls. DNA was obtained from oral mucosa swab samples. MMP-2 genotypes were determined by PCR-based denaturing high-performance liquid chromatography analysis while MMP-9 and TIMP-2 genotypes were identified by a PCR-based restriction fragment length polymorphism. χ2 test after Yates' correction was used to investigate the possible association of the genotypes with the G-AgP. Results: Although gene polymorphisms for MMP-2 and MMP-9 did not show any association with the G-AgP, the analysis of the TIMP-2 −418G to C gene polymorphism revealed significant differences between the patients and controls. Compared with controls, a significant increasing trend of TIMP-2 −418C carrier in the G-AgP patients occurred (p=0.013). Conclusion: It is suggested that the TIMP2 −418G to C gene polymorphism is associated with G-AgP in the Chinese subjects.

We have examined, by immunocytochemical methods and nociceptive behavior assessment in rats, whether astrocytes in the parabrachial nucleus (PBN) are involved in the regulation of traumatic occlusion. The expression of glial fibrillary acidic protein (GFAP) in PBN of ipsilateral and contralateral sides was up-regulated 4 h after occlusal changes in molars, reached peak levels at 24 h, and was then gradually down-regulated. PBN astrocytes activated by traumatic occlusion were found to have enlarged cell bodies and thickened processes within 8 h. An inhibitor of glia metabolism (FCA, fluorocitrate) reduced astrocyte activation and significantly attenuated the development of pain hypersensitivity in this model. The results suggested that the GFAP-immunoreactive astrocytes in PBN within the bridge of Varolius were activated by traumatic occlusion, and that they were involved in the transmission and modulation of nociceptive information in the central nervous system. However, although astrocytes in PBN are thus probably involved in causing post-occlusal hyperalgesia, we have not been able to exclude that astrocytes at other locations also contribute to this effect.

Alzheimer's disease (AD) is the most common neurodegenerative disorder and there is currently no efficient cure for this devastating disease. Cognitive stimulation can delay memory loss during aging and in patients with mild cognitive impairment. In 3 × Tg-AD mice, training decreased the neuropathologies with transient amelioration of memory decline. However, the neurobiological mechanisms underlying the learning-improved memory capacity are poorly understood. Here, we found in Tg2576 mice spatial training in Morris water maze (MWM) remarkably improved the subsequent associative memory acquisition detected by contextual fear conditioning. We also found that spatial training enhanced long term potentiation, dendrite ramification and spine generation in hippocampal dentate gyrus (DG) and CA1 neurons at 24 h after the training. In the molecular level, the MWM training remarkably activated calcium/calmodulin-dependent protein kinase II (CaMKII) with elevation of glutamate AMPA receptor GluA1 subunit (GluA1), postsynaptic density protein 93 (PSD93) and postsynaptic density protein 95 (PSD95) in the hippocampus. Finally, the training also significantly ameliorated AD-like tau and amyloid pathologies. We conclude that spatial training in MWM preserves associative memory capacity in Tg2576 mice and the mechanisms involve augmentation of dendrite ramification and spine generation in hippocampus.

Recent developments of biotechnology have produced a great variety of protein and bioactive drugs. For these drugs to be used therapeutically, suitable drug delivery systems have become increasingly essential. Dextran-derived biomaterials have been considered to be compatible matrices for protein and bioactive drugs because of their hydrophilic properties and ability to control drug dissolution and permeability. A novel class of dextran-glycidylmethacrylate (Dex-GMA)/poly(ethylene glycol) (PEG) microspheres were designed and synthesized by polymerization of Dex-GMA emulsified in an aqueous PEG solution. Dex-GMA was prepared by substituting the hydroxyl groups in Dex by GMA. The drug loading and in vitro drug release was evaluated by routine procedure and the biological activity of BMP-loaded microspheres was studied by experimental cytology methods. Recombinant human bone morphogenetic protein-2 (rhBMP-2) were entrapped in dextran-derived microspheres quantitatively and with full preservation of their biological activity. In vitro release kinetics indicated that dextran-derived microspheres could retain rhBMP-2 in a variable manner depending on the preparation and degradation of the microspheres. The release profiles of rhBMP-2 from microspheres as a function of time showed that rhBMP-2 releasing kinetics in vitro fitted to first-order and Higuchi equations. The release profile in vitro was in accord with two phases kinetics law and more than 60% drug were released during 20 days. Cytology studies showed rhBMP-2 microspheres have good biological effects on cultured periodontal ligament cells, and could achieve a longer action time than concentration of rhBMP-2 solution. These properties make those microspheres interesting osteo-conductive BMP carriers, allowing to decrease the amount of implanted factor required for tissue regeneration.

Recent satellite observations and ground-based observations show that the interplanetary conditions have a strong influence on the FACs of the earth. This paper studies the influence of interplanetary By component on the FACs in the reconnection region of magnetopause by means of 3D MHD simulation. The interplanetary By affects the reconnection process and the related FACs of the simulation region through dayside boundary magnetic field Bby at x = –Lx. Results show the rapid increase of Bby can increase FACs remarkably, sometimes about one order larger. Larger Bby can also maintain FACs at a high level. In addition, the asymmetry of By distribution in the reconnection region caused by Bby gives rise to the asymmetry of FACs. These results are in good agreement with satellite observations. Because FACs at the inner side of the reconnection layer flow into the polar ionosphere along the magnetic field, the results are very important to the better understanding of coupling of Solar wind-magnetosphere-ionosphere.